Yeah much higher bypass ratio. Current turbofans bypass ratio is limited by the fan diameter. With a series hybrid you can power multiple fans from one engine.

Yeah much higher bypass ratio. Current turbofans bypass ratio is limited by the fan diameter. With a series hybrid you can power multiple fans from one engine. Or more likely engines. So you could design a plane with two engines and four fans. For a reaction engines thrust is proportional to mass flow X delta V. And power is proportional to mass_flow X delta V squared. You can see why high bypass turbofans are more efficient. More thrust/less power. Couple of other benefits. Much safer in an engine out condition because you can power your fans off the remaining engine. With a battery hybrid you could power the fans for a limited time with all engines out. Probably less throttle lag with an battery hybrid. Throttle lag is what kills people during take off and landing in bad weather. Wind shear causes the airspeed to drop, pilot needs more power but the engines take seconds to respond. Take off and landing under battery power --> way less noise.